Metal slide fasteners and method of making same



July 11, 1961 A. J. MCNAMARA METAL SLIDE FASTENERS AND METHOD OF MAKINGSAME Filed March 5, 1959 M H. W

United States Patent O 2,991,528 METAL SLIDE FASTENERS AND METHOD OFMAKING SAME Ambrose J. McNamara, White Plains, N.Y., assignor to IrvingConstant, Esq., New York, NY. Filed Mar. 3, 1959, Ser. No. 796,955Claims. (Cl. 24205.16)

The present invention relates to metal slide fasteners and method ofmaking same. More particularly, the present invention relates to amethod of making metal slide fasteners in which the metal slide fastenerelements are provided with a finish after the elements have beenattached to the tapes of the slide fastener.

In the making of metal slide fasteners, it is often desirable to providethe metal slide fastener elements with a finish, such as a protectivecoating, a coloring, and/or a lubricant coating. Such finishes are oftenapplied by an electrolytic process, such as electro-plating, orancdizing. Heretofore, the metal slide fastener elements have been madefrom wire which was provided with the finish prior to forming theelements, or a string of the elements was provided with the finish priorto cutting the elements apart. However, such elements had bare,unfinished spots where the elements had been cut and formed from thewire or string. Also, the slide fastener elements have been completely"formed and then provided with the finish prior to attaching the elementsto the slide fastener tapes. However, this requires the handling of theindividual elements which complicates the .process of attaching theelements to the slide fastener tapes.

It is desirable to apply the finish to the slide fastener elements afterthe elements have been attached to the slide fastener tapes so as toprovide the finish over the entire surface of the elements without thenecessity of handling the individual elements. However, when the finishis applied by an electrolytic process, there is a problem of making goodelectrical contact with the ele- .ments since the elements are'mountedin spaced relation when the finish is applied to the slide fastenerelements after the elements have been attached to the slide fastenertapes, the tapes are brought into contact with the treating,-.chemicals, which may damage the tapes.

It is an object of the present invention to provide a method of makingmetal slide fasteners.

' It is another object of the present invention to provide a method ofmaking metal slide fasteners in which the slide fastener elements areprovided with a finish.

It is still another object of the present invention to provide a methodof making metal slide fasteners .in which 'the slide fastener elementsare provided with a finish after the elements have been attached to theslide fastener tape.

It is a further object of the present invention to provide a method ofmaking metal slide fasteners in which the slide fastener elements areelectrolytically provided with a finish after the elements have beenattached to the slide fastener tape.

It is a still further object of the present invention to provide amethod of making metal slide fasteners in 3 which the slide fastenerelements are provided with a finish after the elements have beenattached to the slide --fastener tape-without damaging the tape.

present invention.

ice

Other objects will appear hereinafter. V For the purpose of illustratingthe invention there is shown in the drawings forms which are presentlypreferred; it being understood, however, that-this invention is notlimited to the precise arrangements and instruof FIGURE 4.

FIGURE 6 is a view illustrating the next step of the method of thepresent invention.

FIGURE 7 is a view illustrating still the next step of the method of thepresent invention.

FIGURE 8 is a view illustrating the final step of the method of thepresent invention. 1

FIGURE 9 is a sectional view through a slide fastener stringer. showinga modification of the methodv of the Referring initially to FIGURE 1,there is shown 'a typical metal slide fastener, generally designated as10. Slide fastener 10 comprises a pair of tapes 12 and 12a of anelectrically non-conducting material, such'as a woven cloth tape. Eachof thetapes 12 and 12a has a welt 14 and 14a respectively along itsinner edge. A plurality of metal slide fastener elements 16 are securedin longitudinally spaced relation to each of the welts 14 and 14a of thetapes l2 and 12a. A slider 18 is movable along the slide fastenerelements 16 to couple and uncouple the elements 16 of the tapes 12 and12a. Slider 18 has a pull tab 20 by which the slider can be moved alongthe slide fastener elements 16. Each of the tapes 12 and 12a with theslide fastener elements 16 secured thereto is referred to as a stringer.

:-method of making a stringer. FIGURE 4 illustrates the first step inthe method of the present invention.

Referring to FIGURE 4, a continuous length tape 12 is movedlongitudinally in the direction of arrow 22. As

the tape .12 moves along, a continuous length strip 24 of anelectrically conductive metal foil, such as aluminum, is placed alongthe welt-14 of the tape 12. :If desired, the metal foil strip 24 mayhave a paper or plastic lining on its side which contacts the welt 14.However,

.001 inch to .003 inch. As shown, the metal foil strip 24 The slidefastener element s- 16 are then placed on the welt 14 of tape 12 andover the metal foil strip 24. As shown in FIGURE 5, each of the metalslide fastener elements 16 is substantially Y-shaped, with the arms 16aof the element 16 receiving the welt 14 of tape 12 and the metal foilstrip 24 therebetween. The arms 16a of slide fastener element 16 arespread apart a distance sufficient to permit the arms 16a tobe placedaround the welt 14 and the metal foil strip 24. However, the arms 16a ofthe slide fastener element 16 have suificient contact with the welt 14and the metal foil strip 24 to hold the slide fastener element 16substantially perpendicular to the longitudinal axis of the welt 14 andto make good electrical contact with the metal foil strip 24.

. FIGURE 6 shows the next step of the-.methodof the present invention,which comprises the process of applying a finish to the metal slidefastener elements '16. a As shown, the process for applying a finish tothe slide fastener elements 16 comprises an electrolytic process forelectro-plating or anodizing the slide fastener elements 16. The tape 12with the metal foil strip 24 and slide fastener elements 16 thereon ismoved in the direction of arrow 28 through "a vessel or tank 30. Thevessel 30 is filled'with an electrolyte, and a cathode 32 of thematerial to be electroplated onto the slide fastener elements 16 is'within the electrolyte. The cathode 32 is connected to the negativeside of a source of electrical energy, not shown. The metal foil stripis connected through a sliding or rolling contact 34 to the positiveside of the source of electrical energy. Thus, the metal foil strip 24and the metal slide fastener elements 16, which are in electricalcontact with the metal foil strip 24, form an anode. Thus, with thesource of electrical energy turned on, as the tape 12 is moved throughthe vessel 30, the metal slide fastener elements 16 are electro-platedwith the material of the cathode 32. The speed of the tape 12 throughthe vessel 30 will determine the thickness of the finish applied to theslide fastener elements 16.

FIGURE 7 shows the next step of the method of the present invention,which comprises securing the slide fastener elements 16 tightly to thetape 12. After the finish has been applied to the slide fastenerelements 16, the arms 16a of the slide fastener 16 are pressed togetherto elamp them tightly around the welt 14. As shown, this is accomplishedby passing the tape 12 and the slide fastener elements 16 between a pairof rams 36. The rams 36 are forced toward each other to engage the arms1621 of the slide fastener element 16, and force the arms 16a togetherto clamp the arms 16a around the welt 14 of tape 12. However, in placeof the rams 36, the arms 16a of the slide fastener element 16 can beforced together by any other means well known in the art, such as apairof rollers or a pair of camming surfaces. As the arms 16a of the slidefastener elements 16 are tightly clamped around the welt 14 of tape 12,the side edges of the arms 16a bite into and cut the metal foil strip24.

FIGURE 8 shows the final step of the method of the present invention. Aspreviously stated, when the slide fastener elements 16 are clampedtightly around the welt 14 of the tape 12, the metal foil strip 24 iscut into small segments by the side edges of the arms 16a of the slidefastener elements 16. The final step of the method of the presentinvention is the removal of the segments of the metal foil strip 24 frombetween the slide fastener elements 16. The tape 12 having the slidefastener elements 16 tightly clamped thereto is passed across arevolving brush 38. The bristles of the brush 38 engage the segments 24aof the metal foil strip 24 which are between the slide fastener elements16, and remove the segments 24a from the welt 14 of tape 12. In place ofbrush 38, :any other suitable means may be used for removing thesegments 24a of the metal :foil strip 24 from the welt 14 of tape 12.

FIGURES 2 and 3 show a portion of the completed slide fastener stringer.The metal slide fastener elements 16 are tightly secured inlongitudinally spaced relation along the welt 14 of'the tape 12. Each ofthe metal slide fastener elements has a coating 40 of the desired finish'over its entire -surface. A small segment 24b of the metal foil strip24 is clamped between each of the slide fastener elements 16 and thewelt 14 of the tape 12. tape 12 can now be cut into desired lengthswhich are assembled with a slider 18 to form the completed slidefastener 10. Since the portions of the metal foil strip 24 which werebetween the slide fastener elements 16 were removed, the flexibility ofthe slide fastener is not impaired.

Referring :to FIGURE 9 there is shown amodification of the method of thepresent invention. A substantially u sha'ped strip 42 of metal :foil isplaced around the welt 14 of tape 12 with the arms 44 and 46 of themetal foil strip 42 extending across the side of the tape 12 for theentire width of the tape 12. The arm 46 of the metal foil strip 42 islonger than the arm 44, and the end 46a of the arm 46 is folded acrossthe outer end of tape 12 and across the end of the arm 44 of the metalfoil strip 42. Thus, the metal foil strip 42 completely encloses thetape .12 and welt 14.

The'slide fastener elements 16 are then placed on the welt 14 and aroundthe base of the metal foil strip 42 in the same manner as described withregard to FIGURE 4. The slide fastener elements 16 are then providedwith a finish in the same manner as previously described with regard toFIGURE 6. Since the tape 12 is completely enclosed in the metal foilstrip 42, as the tape 12 passes through the tank 30, the tape 12 is notexposed to the electrolyte within the tank 30. Thus, the tape 12 cannotbe damaged by the chemicals in the electrolyte. Also, "if the finishingprocess is one to apply a color to the slide fastener elements 16, thecolor of the tape 12 will not be affected by the color being applied tothe slide fastener elements 16. Therefore, the tape 12 can be one color"while a difi'erent color is being applied to the slide fastenerelements 16. After the finish has been applied to the slide fastenerelements 16, the elements 16 are clamped tightly around the welt 14which also causes the metal foil strip '42 -tobe cut along each side ofthe slide fastener elements 16. The metal foil strip 42 is then removedfrom the tape 12 and from the portions of the welt 14 bet-ween the slidefastener elements 16.

Although the method of the present invention is shown and described ascomprising separate individual steps, the steps 'of the method of thepresent invention can be carried out as a single continuous operation.Also, although the method of the present -invention is shown anddescribed with regard to making a slide fastener having a particulartype and shape slide fastener element, it is to be understood that themethod of the present invention is also applicable to making metal slidefasteners having any of the well known type and shape slide fastenerelements.

The present invention may be embodied in other spe- 'cific forms withoutdeparting from the spirit or essential attributes thereof and,accordingly, reference should be made to the appended claims, ratherthan to the foregoing specification as indicating the scope of theinvention.

I claim:

1. A method of making a metal slide fastener having a't'ape with aplurality of slide fastener elements secured in longitudinally spacedrelation to an edge of the tape which comprises placing a strip of metalfoil around the edge of the tape, placing the slide fastener elements inlongitudinally spaced relation around the edge of the tape and incontact with said metal foil strip so that portions 'of said strip willbe exposed, applying a finish to said slide fastener elements, thenclamping said slide fastener elements tightly to said tape, and removingthe exposed portions of said metal foil strip.

2. Amethod of making a metal slide fastener having a tape with aplurality of slide fastener elements secured in longitudinally spacedrelation to an edge of the tape which comprises placing a strip of metalfoil along the edge of the tape, placing the slide fastener elements inlongitudinally spaced relation around the edge of the tape and aroundand in contact with at least a portion of said metalfoilstn'p, applyinga finish to said slide fastener elements, then clamping said slidefastener elements tightly :tosaid tape so as to cause said slidefastener elements to cut through said metal foil strip, and removing theexposed portions of said metal foil strip.

3. A method of making a metal slide fastener having a tape with aplurality of slide fastener elements secured in longitudinally spacedrelation to an edge of the tape which :comprisesplacing a strip of metalfoil along the edge of the tape, placing the slide fastener elements inlongitudinally spaced relation around the edge of the tape and aroundand in contact with at least a portion of said metal foil strip,electrolytically applying a finish to said slide fastener elements, thenclamping said slide fastener elements tightly to said tape so as tocause said slide fastener elements to cut through said metal foil strip,and removing the exposed portions of said metal foil strip.

4. A method in accordance with claim 3 in which the finish is applied tothe slide fastener elements by passing the tape having the metal foilstrip and slide fastener elements thereon through a vessel containing anelectrolyte and a cathode within the electrolyte with the slide fastenerelements passing through the electrolyte, and connecting the metal foilstrip in an electrical circuit with a source of electrical energy andthe cathode.

S. A method of making a metal slide fastener having a tape with aplurality of slide fastener elements secured in longitudinally spacedrelation to an edge of the tape which comprises enclosing said tapewithin a strip of metal foil, placing the slide fastener elements inlongitudinally spaced relation around the edge of the tape and incontact with said metal foil strip, applying a finish to said slidefastener elements, then clamping said slide fastener elements tightly tosaid tape, and removing the exposed portion of said metal foil strip.

6. A method of making a metal slide fastener having a tape with aplurality of slide fastener elements secured in longitudinally spacedrelation to an edge of the tape which comprises enclosing said tapewithin a strip of metal foil, placing the slide fastener elements inlongitudinally spaced relation around the edge of the tape and aroundand in contact with at least a portion of said metal foil strip,applying a finish to said slide fastener elements, then clamping saidslide fastener elements tightly to said tape so as to cause said slidefastener elements to cut through said metal foil strip, and removing theexposed portions of said metal foil strip.

7. A method of making a metal slide fastener having a tape with aplurality of slide fastener elements secured in longitudinally spacedrelation to an edge of the tape which comprises enclosing said tapewithin a strip of metal foil, placing the slide fastener elements inlongitudinally spaced relation around the edge of the tape and aroundand in contact with at least a portion of said metal foil strip,electrolytically applying a finish to said slide fastener elements, thenclamping said slide fastener elements tightly to said tape so as tocause said slide fastener elements to cut through said metal foil strip,and removing the exposed portions of said metal foil strip.

8. A method in accordance with claim 7 in which the finish is applied tothe slide fastener elements by passing the tape having the metal foilstrip and slide fastener elements thereon through a vessel containing anelectrolyte and a cathode within the electrolyte with the slide fastenerelements passing through the electrolyte, and connecting the metal foilstrip in an electrical circuit with a source of electrical energy andthe cathode.

9. A metal slide fastener stringer comprising a slide fastener tape, aplurality of metal slide fastener elements secured in longitudinallyspaced relation to one edge of said tape, and a separate piece of metalfoil clamped between each of said slide fastener elements and said tape.

10. A metal slide fastener stringer comprising a slide fastener tape, aplurality of metal slide fastener elements secured in longitudinallyspaced relation around one edge of said tape, and a separatesubstantially U-shaped piece of metal foil extending around the edge ofsaid tape beneath each of said slide fastener elements and clampedbetween said elements and said tape.

References Cited in the file of this patent UNITED STATES PATENTS2,063,515 Morin Dec. 8, 1936 2,071,603 Winterhalter Feb. 23, 19372,098,651 Sundack Nov. 9, 1937 2,264,580 Morin Dec. 2, 1941

